Necticut



Aeg. `:45, 1925. 1,551,501-

W. L. HURLBURT MEASURING RULE Filed Nov. 2v2, 1923 lllllllll Patented Aug. 25, 1925.

" UNITEDkl STATES V WILLIAM LEWISk HURLBURT, OE NEW BRITAIN, CONNECTICUT, AssIGNOR To THE STANLEY WORKS, or NEW BRITAIN, CONNECTICUT, A CORPORATION OE CON- NECTICUT. y A y MEASURING RULE.

Application filed November 22, 1923.` Serial NO. 676,436.

To all 'whom t may concern:

Be it known that I, WILLIAM LEWIS HURLBURT, a citizen of the United States, and a resident of New Britain, county 'of Hartford, State "of Connecticut, have invented certain new and useful Improvements in a Measuring Rule, of which the following is a specification.

This invention relates to measuring rules, and has particular reference to a head joint hinge for measuring rules, the sections of which are made of wood or the like.

I Ieretofore, in rules of this sort, it has been customary to make the kerfs, which receive the hinge leaves, of a uniform curvature;` that is, of' a single radius. One objection to this arrangement is that, in assembling the parts, diiliculty is experienced in properly alining the hinge leaves and the rule sections to which they are to be attached. This old arrangement requires a specially devised fixture and the use of skill and time to Vbring the leaf into proper position within the rule section; that is, with the straight edge of the leaf in parallelism with the side edge of the rule section to which it is applied. Also, this old arrangement is objectionable in that the wooden rule sections are considerably weakened by the kerfs which are of substantial depth for an appreciable length of the rule. section.

The aim of the present invention is to provide an improved measuring rule wherein the above and other objections incident to rules, as heretofore made, are eliminated. To this end, I so form the kerfs that, in assembling the parts, the hinge leaf may be brought very readily and quickly into proper position in the kerf of the rule section without the use. of a specially devised fixture. For this purpose, the saw kerf is so fashioned as to provide a projection or alining point which corresponds to and is adapted to be received by a notch or recess in the edge of the hinge leaf. In the present illustrative disclosure, the saw kerf is so formed that the bottom wall thereof has two portions struck about different centers and, if desired, thesefportions may be connected by a straight portion, as hereinafter described more in detail. The outer edge of the hinge leaf, which is preferably stamped or cut from sheet metal stock, corresponds in outline t0 thev shape of the bottom'wall of the kerf so as to snugly abut thereagainst.

This. arrangement is also of advantage in that the extent to vwhich the rule section is weakened by thekerf is considerably less than when the kerf is of uniform radius throughout its length. Also, by making the hinge leaf of the configuration described, there is an appreciable saving of materialA in that a larger number of these hinge leaves may be obtained from a giveny amount of sheet metal than would be the case if the leaves were not provided with the notches.

In vthe accompanying drawing, wherein Ik have shown, for illustrativeV purposes, one embodiment which thel present invention may take,

Figure l is a view showing my improved head joint hinge pivotally connecting a pair of rule sections;

Fig. 2 is an end view of the joint, a portion thereof being in section on line 2-2 of Fig. l;

Fig. 3 is a detail view of one of the hinge leaves;

v Fig. 4 is a view of one Of the rule sections, one end of which is broken away on a longitudinalline t0 show the configuration of the kerf; and

Fig. 5 is a side edge view of the rule section shown in Fig. 4. Referring to the drawing in detail, a, a designate rule sections such, for instance, as the two middle sections of a two-foot folding rule. b, b designate the hinge leaves; c, @designate thev .usual washers, and d is a rivet for pivotally connecting the hinge leaves together. e designates the' pins for securing'the hinge leaves in the saw kerfs of the rule sections. v

In accordance with the present illustrative disclosure of the invention, the kerfs in the adjacent' ends of the rule sections f1, ai, and which kerfs are adapted to receive the hinge leaves b, are'so formed as .to provide the rear or bottom wall thereof with a portion l0 curved concentrically to the center of pivot between the rule sections, a second vcurved portion l1, preferably ofthe same radius as the first one 10 but of less depth, and a straight portion 12 connecting the portions l0 and 11. This saw kerf may be Vformed in any suitable way, but, preferably, it is done'by a suitable machine having a saw, the radius of which is the same as the radii of the curved portions 10 and 11.. In .forming the kerf, the curved portion 10 is vlirst cut by feeding the rule section and saw, one relative to the other, until the center of the saw is brought into a position relative to the rule section corresponding to the pivot point between the rule sections, this center in the drawing being indicated by the numeral 15 (see Fig. 4). rlhen the saw is moved outwardly, or away from the rule section, and is then fed longitudinally of the rule section so as to form the straight portion 12 and the curved portion 11. By way of example, it may be assumed that, in forming the straight portion7 the aXis of the saw is moved from the point 16 to the point 17 and that the curved portion 11 is struck about this latter' point.

The hinge leaf, which is preferably stamped or cut from sheet metal to the shape shown in F 1 and 3, has its outer edge pro 'ided with a curved portion 10 struck about the axis 15 of the hinge leaf, a second curved portion 11, and a straight portion 152n between the same, These portions 10a, 11 and 12, respectively, correspond in configuration and relation to the portions 10, 11 and 12 of the bottom wall Aof the lrerf so that, when the parts are assembled, the outer edge of the leaf will engage throughout its length the bottom wall of the lrerf.

lt will be seen that, with the construction described. the bottom wall of the kerf is provided between its ends with a projection 14, and the edge of the hinge leaf is provided with a complementary notch or recess 14a which is adapted to receive the projection 14 when the parts are brought into the assembled position of Fig. 1. Furthermore, .it will be seen, owing to the fact that the portions 10 and 11 of the bottom wall of the kei-f are struck about different centers, and the intermediate portion 12 is straight, and the corresponding portions of the outer edge of the hinge leaf are similarly shaped, there are provided, between the outer' edge of the hinge leaf and the bottom wall of the lerf, three points or lines of engagement which insure proper alinement of the hinge leaf within the kerf. d

It wiil be readily seen, from the foregoing` description taken in connection with the drawing, that, to properly position the hinge leaf in the rule section, it is merely necessary, without the use of any great amount of skill or a specially devised fixture, to slide or push the hinge leaf inwardly and longitudinally of the kerf until the projection 14 tits in the notch 14a. To this extent, the hinge leaf may be said to be capable of self-alinement within the kerf of the rule section. It will further be noted that, owing to the projection 14, the rule sections are weakened to a less extent by the lterf than would be the case if the kerfwere of uniform radius throughout its length, as was the case in measuring rules as heretofore constructed. Furthermore, owing to the fact that the hinge leaf is recessed or notched, as at 14a, there is a` saving in metal, permitting a greater number of these hinge pieces to be stamped from a given area of sheet metal.

Thus, it will be seen that the stated objects of the invention are obtained, a stronger rule being provided at a lesser eX- pense.

As many changes could be made in the above construction and many apparently widely different embodiments of this invention could be made without departing from the scope thereof, it is intended that all matter contained in the above description or shown in the accompanying drawing shall be interpreted as illustrative and not in a limiting sense.

i t is also to be understood that the lanlguage used in the following claims is intended to cover all of the generic and specific. features of the invention herein desc 'ibed and all statements of the scope of the invention which, as a matter of language. might be said to fall therebetween.

l claim as my invention:

1. A head joint hinge for measuring rules comprising a rule section having a saw herf, the bottom wall of which comprises different arcuate portions having different centers, and a hinge piece having an edge corresponding in shape to and adapted to engage against the bottom wall of said lierf.

n.. head joint hinge for measuring rules comprising a rule section having a saw lierf, the bottom wall of which has one portion cut about a center corresponding to the line of pivot between the rule sections and another portion cut on the same radius about a center spaced outwardly and forwardly of the first center, and hinge leaf having its outer edge provided with portions struck about centers respectively corresponding to the centers about which said portions of said korf are cut and adapted to snugly engage the bottom wall of said lrerf.

3. A head joint hinge for measuring rules comprising a rule section having a saw kerf, the bottom wall of which has one portion cut about a center corresponding to the line of pivot between the rule sections and another portion cut on the same radius about a center spaced outwardly and forwardly of the first center, and a hinge leaf having its outer edge provided with portions structr about centers respectively corresponding to the centers about which said portions of said lrerf are cut and adapted to snugly engage the bottom wall of said kerf, said bottom wall, of said kerf also having a straight portion between said curved portions, and Jrhe outer edge of said leaf having a similar straight portion.

vWILLIAM LEVIS HURLBURT. 

